I-680 going south, near I-680 and I-480 junction there will be lanes for exits to West Center Street, "I" Street, "L" Street, and "Q" Street. After driving into the said service lane, the lane contains an island on the right hand side. The trooper will usually be on the island zapping people as the exit lanes has posted speed limit of 50 MPH compared to 60 MPH for the main strech of highway. During the dusk and dawn the darkness of the island can be a good cover for the troopers.